Hydraulic molding press



J. VAN HLLEN HYDRAULIC MOLDING PRESS Sept. 23 1924.

Filed Oct. 9, 1922 Patented Sept. 23, 1924.

PATENT OFFICE.

JOSEF vim HLLEN,` or CREFELD, GERMANY.

HYDRAULIC MOLDING PRESS.

Application filed October 9, 1922. Serial No. 593,411.

To all whom t may concern.:

Be it known that I, JOSEF VAN HLLEN, a citizen of the German Republic, residing at Crefeld, Germany, have invented certain new and useful Improvements in Hydraulic Molding Presses, for which an application was filed Sept. 19, 1921, in Germany, by Nieder, and of which the following is a specification. y i

This invention relates to a double-acting hydraulic molding press ,for the manufacture of articles from a raw substance, such.

as celluloid, caoutchouc, soft metals and sheet metal or similar plastic or mouldable materials. A v

It is known in the art to produce from celluloid or caoutchouc e. g. combs with the aid of a molding press. It is common practice to employfor the purpose single acting hydraulic presses and comb moulds comprising each an upper and a lower part or half recessed to conform to the shape of the comb to be made. The process of making combs with the aid of said presses is very troublesome. Preliminarily the two halves or parts of the mould are heated by placing them upon heating plates which in turn are heated by means of steam or hot water. The temperature up to which the moulds are to be heated depends upon the material to be employed and is determined by fingertest. As soon as the heating of the mould has been continued for a length of-time to ensure the desired temperature, a plate yor sheet of celluloid or caoutchouc which likewise had been heated previously, is laid upon the lower half of the mould, the upper mould part is thereafter placed thereupon and the thus assembled mould halves with the heated sheet of shapable material lbetween them. is placed in the press. The pressing operation finished, the mould is cooled by means of cold water led into and through the hollow upper pressing plate with which the mould is in contact so as to be cooled indirectly throu h the agency of the said ressing. plate. he mould is then removed) from thepress in order to be opened by means of suitable tools so that the comb can be taken out.

The above described process is very dei' 4 efore all it is irn-` possible for the operator to always obtain.

cient and imperfect.

any other articles made are of unequal quality and much time is lost in assembling the mould parts and placing them in the press. After the pressing operation a length of time is to be spent in waiting for the mould belng cooled and the subsequent opening of the firmly cohering halves of the mould also involves a good deal of work.

` The object of my invention is to remedy the stated defects of the presses hitherto in use. The eiciency of the improved press embodying my invention is greatly. increased by its construction in the form of a double acting .hydraulic machine provided with a movable systemof pressure pistons adapted to work alternately in opposite directions and furtherprovide with a single pressing plate or a purality of pressing plates or tables, the upper and lower faces of which are adapted to alternately cooperate with upper and lower stationary counter-plates or abutments. This method of alternately working in two directions affords a way for preparlng and dressing the moulds on the one side for the subsequentvpressing o eration, while at the same time the moul s on the other side are in operation. In -the new machine the moulds are directly heated and chilled by means of suitable uids such as steam and water, respectively, passing therethrough, and a double valve control is provided in connection with a hand lever for causing at the same time the one mould or series of moulds to be heated and the other one to be chilled and vice versa. The conduits are arranged in a manner that when the cooling medium is applied to the mould the pressed comb therein will be chilled to solidify or harden first at and from the teeth across towards lthe back of the comb with the result that immediately upon the beginning of the chilling action there will be no 'ossibility for material to flow ofi'. Furt ermore, the moulds are constructed and arranged in a ymanner that any material squeezed out from the mould and sticking to the latter can bereadily removed therefrom.

The invention relates to other details also which will be fully vdescribed hereafter.

' In the accompanying drawin s:-

Figure 1 is a front view of t e improved press provided with -the controlling means for the heating and chilling of the moulds, and with the conduits for the heating and chilling media shown diagrammatically Azo only; Figure 2 is a side view of the one part or half of a mould; Figure 3 is a plan of the same; Figure 4 is a sectional view of a mould part or half and Figure 5 is a crosssectional view thereof.

The drawings illustrate by way of example a machine equipped with a single table only, but for persons skilled in the art it Will be easily understood from the following description how the machine is to be altered and works if a further table would be arranged therein.

Mounted between the two pressing cylinders a and b is a table c connected with the pistons d and e of the said cylinders through rods f and g and by means of cross-heads h and z' to form a rigid movable system, so that if the cylinder a is supplied with pressure fluid, the table is caused to move upwards, while at the same time the piston d is caused to go back into its cylinder and a pressing operation is brought about between the table and the counter plate or abutment connected with the upper cylinder a. On the other hand, the table will move downwards in case that the cylinder b is supplied with pressure fluid and consequently a pressing operation will be brought about between the table and the counter plate or abutment connected with the lower cylinder b. Figure 1 shows the parts of the machine in the latter condition. As will be seen there are two pairs of operating or. pressing surfaces provided in the machine and in case of a compound machine having a plurahty of pressing tables e. g. two such tables, there will be two roups of operating pairs of surfaces one ofgwhlch, in each pair 'is free and ready for being prepared or dressed for a subsequent pressing operation, whilst the other one is in actuation.

The efficiency of the machine can be multiplied by providin a plurality of tables 0 -in connection with t e rods f and g between pressing cylinders such as or similar to and b. In case of providing two tables c with a further stationary do-uble acting abutment or counter-plate arranged therebetween on the stationary framing, each tablewill be caused to reciprocate between the counter-plate of the correspondmg pressing cylinder and the stationary abutment or counter-plate interposed between the two tables. l c

Upper and lower mould halves are prov1ded on the table or tables and on the abutments or counter-plates, and the embodiment shown the upper moulds are actuated or workin at the upward stroke of the pistons and t e lower moulds are active at the downward stroke of the pistons.

` The mould recessed to the required shape for the manufacture of combs com rises, as hereinbefore stated, two parts or alves, a lower half k and an upper half Z. In the embodiment of the invention shown in the drawings the lower halves lc of the moulds are rigidly connected with the lower abutment or counter-plate b and with the upper surface of the table o, respectively, and the upper halves Z are firmly connected with, the upper abutment or counter-plate a and with' the lower surface of the table 0. The single mould halves are provided with registering pins m adapted to engage in correspondingly shaped holes provided in the opposed or co-operating halves of the moulds so that an absolutely accurate assemblage of the co-acting halves will be ensured for the subsequent pressing operation.

The two halves of the mould are each provided with passages or channels for the circulation of the heating or cooling fluid and also distributing chambers, not shown in the drawings may be arranged therein. In the constructlon of the mould shown by way of example in Figures 2 to 5 and intended for the manufacture of combs four comb shaped recesses are provided therein both in the upper half and in the lower half correspondingly, for the production of four combs at each single pressing operation. In accordance therewith four inlets or admission passages n, Fig.` 4 and 5 for the chilling and the heating Huid are provided in each half below the four rows of teeth of the said four recesses arranged infpairs, but two exhaust or exit passages 0 only are disposed therein below the longitudinal median line between the backs of each pair of recesses and communicatin with the passages a so that the supplied eating or cooling fluid flowing in and through a pair of passages n will flow out through the one exit assa e o communicating therewith and the uid owing through the other pair of passages n will flow out through the other exit passage 0. Owing to the described construction the supplied chilling fluid acts to first cool down and harden-the material in the comb-sha ed recesses at the teeth portions thereof an to then cool and harden the back portions of the combs. As soon as the. cooling fluid is admitted the plastic material between the two mould halves will be prevented from protruding beyond the joints of the mould.

The operation of the machine is as follows: Figure l shows as above stated, a machine with a single table c and in the operating position with the lower set of moulds in pressing condition and heated, that is to say, supplied with steam to keep the material in plastic condition. Steam is supplied, by any suitabley conduit from any suitable source, at D to the slide valve p to flow through the piping g, a non-return valve r and a stationary conduit into stationary mould halves of the lower pressing cylinder b, and through a flexible conduit s into the movable mould portions atached to the bottom surface of the table o. The steam flows through all of the interconnected single moulds, further through the conduits t and u, the slide valve 'v and a pipe D1. ofl' to a condenser or the like.

At the same time the upper set of moulds 4are maintained in opened position and subject to the action of a cooling fluid. The latter is supplied by means of any suitable conduit at W to the slide valve w in order to flow through the piping a non-return valve y and a stationary conduit into the stationary mouldhalves Z of the upper pressure cylinder a, and through a flexible conduit e into the movable mould halves 7c attached to the top surface of the table c.

The chilling fluid leaves the mould'halves through a flexible conduit l and a stationary or rigid conduit 2, respectively, to flow into a slide valve 3 and therefrom ofl' into a conduit W1. All of the `four slide valves are positively connected through suitable rods with a common controlling lever or handle 4 so that the entire valve system is under the control of a single number. y

When the pressing operation at the lower side of the table c is completed and the moulds at the upper side ofthe table have been properly dressed and filled in the mean time, thecourse of the heating and chilling fluids ischanged by the means of the reversing lever 4. To this end the said lever is moved in the direction of the arrow I andl thereby the set of upper moulds is supplied with steam or hot water' whilst the set of lower moulds receive cold water or any other suitable chilling fluid. Thereupon the machine is reversed so that the upper moulds will become active or closed and the lower moulds opened to allow of the pressed combs being removed therefrom.

The machine' as shown in the drawings is constructed to operate four moulds, two at each stroke, and each mould comprises four recesses so that eight combs will be made at each stroke. It goes without saying that the number of moulds in the machine is immaterial inasmuch as any desired or suitable number of mgllds may be employed'in conformity with the si`ze of the machine or the size of the moulds desiredto be given. lIn

`case of socalled double moulds, as shown in Figures 3 and 4, a groove or channel 5 may be provided `between the two pairs of combshaped recesses to afford a means for readily removing all and any material that4 may have been squeezed out from the toothed edges of the two innermost recesses. To this end ay rod or'plunger may be employed for manually pushing out said material from the -channel or channels 5.

It is obvious that-changes might be resorted to in the form and arrangement of the several parts of the machine and of fthe moulds employed therein, without departingv from the spirit and scope ofA my invention, hence I do not wish to limit myself strictly to the structure herein shown and described, but

1 A hydraulic press for making, by`

vcross-heads connecting the pistons to form a bodily movable system, a pressure table rigidly connected with said rods intermediate between'the cross-heads and pistons, and stationary abutments adapted to cooperate' with the two surfaces of the said :pressure table.

3. A hydraulic press for making, by means of moulds, articles from shapable raw materials such as Celluloid, caoutchouc, soft metals, sheet mteal, comprising two reciprocating pressure pistons, rods and cross-heads connecting the 4pistons to form a bodily movable system, a pressure table rigidly connected with the said rodsintermediate between the pistons, va stationary cylinder for each of the two pistons to work in and stationary counter-plates rigidly connected with the -said cylinders to serve as abutments for co-operation with the two surfaces of the said table.

4. A hydraulic press for making, by means of moulds, articles, from shapable materials such as Celluloid, caoutchouc, soft metals, sheet metal, comprising two reciprocating pressure pistons onemounted above the other in vertically axial alinement, cross-heads connected with the outer ends-of said Ipistons, rods connecting oppo. site ends --of said cross-heads to form a bodily movable system, a pressure table rigidly connected with the said rods intermediate between the two pistons, a stationary cylinder for each piston to work in nd stationary counter-plates rigidly connected with the said cylinders to serve as abutments for co-operation with the two surfaces of the said pressure table.

5. A hydranlic'molding press, comprising two reciprocating pressure pistons, crossheads l'connected wlth the outer ends of said pistons, rods connectingopposite ends of said cross-heads to hold the pistons in vertically axial alinement and to form a bodily movable system, a plurality ofrpressure tables rigidly connectedV with the said rods in intervals .intermediately 4between the two pistons, a stationary cylinder for each piston to work in, an separate stationary counter-plates rigidly connected with each' cylinder and rigidly mounted, respectively, between two tables.

6. The combination, in a hydraulic molding press, of the reciprocating table carrying the one half of the moulds, the stationary counter-plates carrying the registering other half ofthe moulds, passages, n, o, in the mould halves, conduits connecting said passages with sources of a heating and a chilling fluid, and a system of controlling valves in said conduits substantially as described.

7. The combination, in a hydraulic molding press, of the reciprocatory table carryingr the one halt` of the moulds, the

stationary counter-plates carrying the registering other half of the moulds, passages, a, o, in the mould halves, conduits connecting said passages with sources of supply, a pair of valves in the conduits simultaneously operable for the circulation of the heating fluid through the moulds, a pair of valves in the conduits simultaneously operable for the circulation of the chilling Huid through the valves, rods connecting the said valves in pairs, a means connecting said rods, and a handle in connection with said means for positively controlling the valve system to alternately supply the moulds with the heating and the chllling fluid.

lIn testimony whereof I aix my signature.

JOSEF VAN HLLEN. 

